More than 300 years ago, three African-born slaves died on the Caribbean island of Saint Martin. No written records memorialized their fate, and their names and precise ethnic background remained a mystery. For centuries, ...

(Phys.org) —Eric Delwart of the Blood Systems Research Institute in San Francisco and colleagues have found two 700-year-old viral sequences in frozen caribou dung in an arctic ice patch. The researchers isolated part of ...

The setting: Europe, about 7,500 years ago. Agriculture was sweeping in from the Near East, bringing early farmers into contact with hunter-gatherers who had already been living in Europe for tens of thousands of years.

(Phys.org) —Scientists who study past pandemics, such as the 14th century Black Death that devastated much of Europe, might soon be turning to an innovative biological detection technology for some extra help.

It is hardly possible to talk about fossil insects in amber without the 1993 movie Jurassic Park entering the debate. The idea of recreating dinosaurs by extracting DNA from insects in amber has held the fascination of the ...

Scientists were surprised at how fast bacteria developed resistance to the miracle antibiotic drugs when they were developed less than a century ago. Now scientists at McMaster University have found that resistance has been ...

Genetic variation due to DNA mutation is a driving force of adaptation and evolution, as well as a contributing factor to disease. However, the mechanisms governing DNA mutation rate are not well understood. In a report ...

After extracting ancient DNA from the 40,000-year-old bones of Neanderthals, scientists have obtained a draft sequence of the Neanderthal genome, yielding important new insights into the evolution of modern humans.

Ancient DNA

Ancient DNA can be loosely described as any DNA recovered from biological samples that have not been preserved specifically for later DNA analyses. Examples include the analysis of DNA recovered from archaeological and historical skeletal material, mummified tissues, archival collections of non-frozen medical specimens, preserved plant remains, ice and permafrost cores, Holocene plankton in marine and lake sediments, and so on. Unlike modern genetic analyses, ancient DNA studies are characterised by low quality DNA. This places limits on what analyses can achieve. Furthermore, due to degradation of the DNA molecules, a process which correlates loosely with factors such as time, temperature and presence of free water, upper limits exist beyond which no DNA is deemed likely to survive. Current estimates suggest that in optimal environments, i.e environments which are very cold, such as permafrost or ice, an upper limit of max 1 Million years exists. As such, early studies that reported recovery of much older DNA, for example, from Cretaceous dinosaur remains, have been proven to be wrong, with results stemming from sample or extract contamination, as opposed to authentic extracted DNA.